Maximum Number Of The Slave Device - Delta EtherCAT Programming Manual

EtherCAT Introduction

2.1 Maximum number of the slave device

Delta EtherCAT master has two types of operation system, RTX real-time operating system from
2
PAC and EtherCAT PCI motion card. Since the operational efficiency among both differs from
one another, the connected slave number is different.
When EtherCAT master runs in RTX real-time operating system, the default of its communication
cycle is 1 ms (1K) and can connect up to remote modules and 64 motion axes, including servo
drives and pulse modules. There is no limitation on quantity of the device that connects to
EtherCAT master. However, if the communication cycle is shorter, the suggested maximum
number of the connected slave will be reduced in accordance with proportion. Please refer to
table 2.1.1 below for the suggested maximum slave quantity to avoid communication instability.
When EtherCAT master runs in PCI motion card, it can connect 64 remote modules and 32
motion axes at most with the default communication cycle 1 ms (1K). Please refer to table 2.1.2.
Communication cycle (ms)
Communication cycle (ms)
2-2
EtherCAT master runs in RTX real-time operating system of Delta PAC
Max. number of the connected
4 ms
2 ms
1 ms
0.5 ms
0.25 ms
0.125 ms
Table 2.1.1 Suggested number of the slave
EtherCAT master runs in Delta PCI EtherCAT motion card
Max. number of the connected
4 ms
2 ms
1 ms
0.5 ms
0.25 ms
0.125 ms
Table 2.1.2 Suggested number of the slave
remote module (1 ms)
100
100
100
50
25
22
remote module (1 ms)
64
64
64
32
16
8
EtherCAT Programming Guide
Max. number of the connected
motion axis (1 ms)
64
64
64
32
16
8
Max. number of the connected
motion axis (1 ms)
32
32
32
16
8
4
March, 2017